Electric shaving devices are used for removing hair from different parts of the body. A typical shaver type is a trimmer-foil-trimmer assembly, as shown in FIG. 1, comprising pre-trimming trimmers, for trimming longer hairs, positioned either side of a shaving foil, for cutting short hairs, so that the shaver can be moved in two directions and performs a two-stage cutting process of pre-trimming and then shaving hairs.
Typically, a pre-trimmer comprises stationary cutting teeth and moving cutting teeth that cooperate to trap and cut hairs that pass between the cutting teeth. Such an example of this arrangement can be seen in U.S. Pat. No. 4,724,614 which discloses a row of stationary cutting teeth adjacent to a row of moving cutting teeth. The stationary teeth protrude further than the moveable teeth and contact the skin of the user to prevent direct contact between the moveable cutting teeth and the skin which will cause irritation. The stationary teeth are positioned above the moveable teeth, with respect to the skin, so that hair is cut as short as possible. However, this arrangement does not entirely prevent the moveable cutting teeth from contacting the skin and causing irritation or damage. Furthermore, the stationary teeth may have sharp edges and may be small enough to catch on some features on the surface of the skin, so as the shaver is moved across the skin the stationary teeth may cause damage and irritation.
Therefore, it is desirable to provide a hair trimming device to substantially alleviate irritation of the skin due to the moveable or stationary cutting teeth.
It is known from WO 2009/024900 A1 to provide a hair trimming device comprising fixed cutting teeth, mobile cutting teeth and a stationary guard to protect the skin from the ends of the fixed teeth as the shaver is moved across the skin. The guard is positioned over a surface of the fixed teeth facing away from the skin and also extends over the ends of the fixed teeth to prevent the fixed teeth from digging into and damaging the skin as they are moved across the skin. The present invention seeks to further improve the performance of the hair trimming device of WO2009/024900 A1 by further reducing contact between the skin and the mobile cutting teeth.
It is known from U.S. 2011/0016723 A1 to provide a hair trimmer comprising protective teeth, fixed cutting teeth and mobile cutting teeth whereby the protective teeth are positioned between the skin and the fixed cutting teeth and the mobile cutting teeth are adjacent to the fixed cutting teeth on the side opposite to the skin. This arrangement results in good protection of the skin but means that the cutting plane (between the fixed and moveable cutting elements) is substantially removed from the surface of the skin and so the remaining hair length may be unsatisfactory.
The present invention seeks to alleviate or substantially reduce the problems described above.